In a study done they probed the political views of 90 university students who later had brain scans. What they found is that those who claimed they were liberal had a larger anterior cingulate cortex. That is the area of the brain responsible for processing conflicting information. Those who claimed to be conservative had a larger amygdala. That is the area responsible for recognizing threats.
Lead author Kanai and colleagues wrote:
“Individuals with a large amygdala are more sensitive to fear,” and might therefore be “more inclined to integrate conservative views into their belief system. On the other hand, our finding of an association between anterior cingulate cortex volume and political attitudes may be linked with tolerance to uncertainty” — which may allow people to “accept more liberal views.”
Dr. Marco Iacoboni professor of psychiatry and biobehavioral sciences at UCLA and director of the Transcranial Magnetic Stimulation Lab at the Ahmanson-Lovelace Brain Mapping Center, has been using brain imaging to study political differences since 2004. He stated:
“To me it makes a lot of sense. We have these tendencies to think our thoughts come out of nowhere, but they actually come from our biology. I’m glad to see liberals have a large anterior cingulate cortex — the more sophisticated part of the brain. The amygdala, on the other hand, is a “really old structure, and not as developed.”
Political Views Reflected in Brain Structure (http://abcnews.go.com/Health/MindMoodNews/political-views-tied-brain-structure/story?id=13317961#.T0v5wvVuDcy)